how do I get my black beans super shiny while still having that nice thick consistency?

I'm not sure I understand when you say thick consistency - do you want the beans to break down a little or remain whole? I haven't had a pressure cooker in 20 years, but when I did I always found that beans cooked really nicely when pressure cooked. They remained whole and retained their shape but they cooked perfectly, not too hard not too soft. But I don't know about shiny? My mind goes to dressing them in something with oil and/or sugar and/or glycerin?

when I say thick I mean the liquid in which they are cooked. The tradition is to puree a small portion of the beans to release the starch and thicken the bean liquid. I tried olive oil as well as mounting the mix a la minute with butter, but neither were really all that successful. I was think a slurry of corn starch might give it a really nice shine, but Im skeptical...